The proposed research addresses how cognitive structures are relevant in furthering the understanding of how spatial knowledge is represented in memory. As spatial knowledge is a basic component to normal adult functioning, understanding of its structure is critical to the understanding of cognitive capabilities of both mentally deficient and physically impaired adults. This proposal focuses on two cognitive structures: the segmentation of space into clusters and the use of reference points. Specifically, this proposal examines 1) the interaction of semantic labels and spatial locations on the creation and use of spatial segmentation, 2) the effect of spatial segmentation itself on task performance and 3) the role of reference points on spatial computations. Segmentation of space will be examined in a map learning context through spatial performance tasks, while the use reference points will be tested in the natural context of distance estimation between North American cities. The results should clarify how cognitive structures can assist and/or bias spatial judgments. The knowledge gained will be directly applicable to the understanding of spatial knowledge and more generally applicable to the understanding of human information processing.